The present invention is directed to an apparatus for use with an inflow cannula of a ventricular assist device.
Each year in the United States, about 2000 or so patients with end-stage heart failure receive heart transplants. Unfortunately, there are another 30,000 to 100,000 patients who could benefit from a heart transplant, but who do not receive a donor heart due to, among other things, limited supply.
One alternative that many clinicians are employing to combat the short supply of donor hearts is the temporary implantation of a ventricular assist device (VAD) such as a left ventricular assist (LVA) pump. The LVA pump draws blood from the left ventricle and pumps the blood into the aorta. The LVA pump shares the load on the ventricle, which allows the heart to xe2x80x9crestxe2x80x9d. While resting with the assistance of the LVA pump, the damaged heart muscle can even start to repair itself. In a few cases, the heart has been able to sufficiently repair itself such that the LVA pump could be removed and the patient no longer needed a transplant. In other cases, the LVA pump stabilizes the patient""s condition and, in lieu of a heart transplant, remains implanted, thereby becoming more of a permanent solution than a temporary solution.
For a number of reasons, it is desirable that the inflow cannula, which is the part of a VAD that is fluidly connected to the heart, be occludable so that blood flow through the VAD can be temporarily blocked. For example, the ability to occlude blood flow through the inflow cannula is needed in cases where the VAD has allowed the heart to heal itself and the VAD is to be removed. In such cases, it can also be desirable to be able to close and seal the inflow cannula, but leave it attached to the heart so that the opening in the heart through which the inflow extends does not have to be closed. It is also desirable to be able to temporarily occlude blood flow through the inflow cannula in cases where the VAD is xe2x80x9cpermanentxe2x80x9d because parts of the VAD may need to be serviced or replaced over time.
The present invention is an apparatus for use with an inflow cannula of a ventricular assist device (VAD). The inflow cannula has a first part for connecting with a ventricle of a heart and a second part for connecting with the VAD. The apparatus comprises a conduit made of a flexible material. The conduit has oppositely disposed first and second ends and a main body portion intermediate the ends. The main body portion of the conduit is movable between a radially collapsed closed condition in which blood flow through the conduit is blocked and a radially expanded open condition in which blood flow through the conduit is not blocked. First connecting means connects the first end of the conduit to the first part of the inflow cannula. Second connecting means connects the second end of the conduit to the second part of the inflow cannula.
According to one aspect of the invention, the main body portion has an accordion-like configuration to allow for relative axial and radial movement of the ends.
According to another aspect of the invention, the first connecting means comprises a first nut for threadedly engaging threads on the first part on the inflow cannula.
According to another aspect of the invention, the second connecting means comprises a second nut and a threaded adapter. The adapter has a first threaded portion for engaging threads on the second part of the inflow cannula and a second threaded portion for threadedly engaging the second nut.
According to another aspect of the invention, the first end of the conduit is sandwiched between threads on the first nut and the threads on the first part of the inflow cannula.
According to another aspect of the invention, the second end of the conduit is sandwiched between threads on the second nut and the second threaded portion on the adapter.
According to another aspect of the invention, the apparatus further comprises means for occluding blood flow through the conduit.
According to another aspect of the invention, the means for occluding blood flow comprises a surgical clamp.
According to another aspect of the invention, the means for occluding blood flow comprises a plug connected to the second connecting means.
According to another aspect of the invention, the apparatus further comprises means for preventing relative axial and radial movement of the ends of the conduit.
According to another aspect of the invention, the means for preventing movement of the ends comprises sutures that extend between the first and second connecting means and secure the first and second connecting means to each other.
According to another aspect of the invention, the first connecting means comprises an adhesive for bonding the first end of said conduit to the first part on the inflow cannula.
According to another aspect of the invention, the second connecting means comprises a rotating seal disposed at the second end of the conduit. The rotating seal is for sealingly engaging the second part of the inflow cannula and for allowing rotation of the second part relative to the rotating seal.
According to another aspect of the invention, the means for preventing movement of the ends comprises a hinged clamshell-style sleeve that encloses the first and second connecting means and holds the main body portion of the conduit in an axially compressed condition.
According to another aspect of the invention, the means for preventing movement of the ends comprises a collar that connects the first and second connecting means to each other.
The present invention also provides an apparatus for use with an inflow cannula of a ventricular assist device (VAD). The inflow cannula has a first part for connecting with a ventricle of a heart and a second part for connecting with the VAD. The apparatus comprises a conduit having oppositely disposed first and second ends and a main body portion intermediate the ends. The main body portion has a resiliently flexible section that is compressible to a closed condition in which blood flow through the conduit is blocked. First connecting means connects the first end of the conduit to the first part of the inflow cannula. Second connecting means connects the second end of the conduit to the second part of the inflow cannula.
The present invention also provides an apparatus for use with an inflow cannula for directing blood flow from a heart to a ventricular assist device (VAD). The inflow cannula has a first part for connecting with a ventricle of the heart and a second part for connecting with the VAD. The apparatus comprises a conduit made of a flexible material. The conduit has oppositely disposed threaded first and second ends and a main body portion intermediate the ends. The main body portion is movable between a radially collapsed closed condition in which blood flow through the conduit is blocked and a radially expanded open condition in which blood flow through the conduit is not blocked. A first nut is circumferentially disposed about the first end of the conduit for connecting the first end to the first part of the inflow cannula. A threaded adapter connects to the second part of the inflow cannula. A second nut is circumferentially disposed about the second end of the conduit and connects the second end to the adapter.
The present invention further provides an apparatus for use with an inflow cannula for directing blood flow from a heart to a ventricular assist device (VAD). The inflow cannula has a first threaded part for connecting with a ventricle of the heart and a second threaded part for connecting with the VAD. The apparatus comprises a conduit having oppositely disposed threaded first and second ends and a main body portion intermediate the ends. The main body portion has a resiliently flexible section that is compressible to a closed condition in which blood flow through the conduit is blocked. A first nut is circumferentially disposed about the first end of the conduit for connecting the first end to the first threaded part of the inflow cannula. A threaded adapter connects to the second threaded part of the inflow cannula. A second nut is circumferentially disposed about the second end of the conduit and connecting the second end to the adapter.
The present invention further provides an apparatus for use with an inflow cannula of a ventricular assist device (VAD). The inflow cannula has a first part for connecting with a ventricle of a heart and a second part for connecting with the VAD. The apparatus comprises a conduit made of a flexible material. The conduit has oppositely disposed first and second ends and a main body portion intermediate the ends. The main body portion has an accordion-like configuration to allow for relative axial and radial movement of the ends. First connecting means connects the first end of the conduit to the first part of the inflow cannula. Second connecting means connects the second end of the conduit to the second part of the inflow cannula. Means for occluding blood flow through the main body portion of the conduit is also included.
The present invention further provides an apparatus for use with an inflow cannula for directing blood flow from a heart to a ventricular assist device (VAD). The inflow cannula has a first part for connecting with a ventricle of a heart and a second part for connecting with the VAD. The apparatus comprises a conduit made of a flexible material. The conduit has oppositely disposed first and second ends and a main body portion intermediate the ends. The main body portion has an accordion-like configuration to allow for relative axial and radial movement of the ends. A first nut is circumferentially disposed about the first end of the conduit for connecting the first end to the first part of the inflow cannula. An adapter connects to the second part of the inflow cannula. A second nut is circumferentially disposed about the second end of the conduit and connects the second end to the adapter. Means for occluding blood flow through the main body portion of the conduit is also included.
In accordance with another embodiment, the present invention also provides an apparatus for use with a ventricular assist device (VAD). The apparatus comprises an inflow cannula having a first part for connecting with a ventricle of a heart and a second part for connecting with the VAD. A conduit made of a flexible material has oppositely disposed first and second ends and a main body portion intermediate the ends. The main body portion has an accordion-like configuration to allow for relative axial and radial movement of the ends. First connecting means connects the first end of the conduit to the first part of the inflow cannula. Second connecting means connects the second end of the conduit to the second part of the inflow cannula. The apparatus further comprises means for occluding blood flow through the inflow cannula.